Steel retainer



Oct. 1, 1929.

F. M. SLATER STEEL RETAINER Filed Dec. 14, 1928 JZ EE PM fi 3: a

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fils ATTORNEY- Patented 0st. 1, 1929 UNITED STATES PATENT OFFICE FRED M.SLATER, OF EASTON, PENNSYLVANIA, ASSIGNOR TO INGERSOLL-RAND COM- PANY,OF JERSEY CITY, NEW JERSEY, A CORPORATION OF NEW JERSEY STEEL RETAINERApplication filed December 14, 1928.

This inventionrelates to rock drills, but more particularly to a steelretainer adapted to be attached to rock drills of the type in which thehammer piston reciprocates independently of the drill steel.

The objects of the invention are to protect the casing parts of the rockdrill against the wearing action of the retainer and to improve uponretainers of this type.

Other objects will be in part obvious and in part pointed outhereinafter.

In the drawings illustrating the invention and in which similarreference characters refer to similar parts,

Figure l is a side elevation in section of a portion of a rock drillhaving the invention applied thereto,

Figure 2 is a front elevation partly in section of the forward end of arock drill and the retainer, and

Figure 3 is a transverse view taken through Figure 2 on the line 33looking in the direction indicated by the arrows.

Referring to the drawings, A represents the cylinder of a drill to whichis secured a front head B by means of side bolts C. A front cylinderwasher D is interposed between the cylinder A and the front head B tohold these elements in coaxial relationship with each other and has abore E through which extends slidably the extension F of a hammer pistonG in a cylinder A.

The front head B acts as a housing for chuck mechanism designatedgenerally by H for guiding a working implement J against which thehammer piston G is adapted to strike. The working implement J may be adrill steel and in this instance is of polygonal form to correspond to apolygonal bore K in the chuck I-I into which the shank L of the drillsteel J extends. At the jimcture of the body portion of the drill steeland the shank L is a collar 0 which, when the drill steel J is fullyretracted, abuts the front end of the chuck to limit the distance whichthe shank L may extend into the front head.

On one side of the front head B is an enlargement P in which is formed atransverse aperture Q, of oblong shape. Preferably the ends R of theaperture Q, are of semi-circular Serial No. 325,938.

form and the sides S of the aperture are tangent to the semi-circularends R and parallel with respect to each other.

Means are provided for limiting reciprocatory movement of the drillsteel J relatively to the front head B and to insure the retention ofthe drill steel in the front head. This means comprises a yoke T whichpartly encircles the drill steel J forwardly of the collar O and sidearms U integral with the yoke T extending rearwardly along the sides ofthe enlargement P. In the rearward or free ends of the side arms U areholes V to receive the ends of a shaft IV which lies in, the uppermostportion of the aperture Q to form a pivot for the yoke T.

The retaining means so far described are in most essential respectssubstantially like that disclosed and described in United States PatentNo. 1,671,133 for steel retainer granted to F. M. Slater, May 29, 1928.The instant invention, however, differs from the afore said patent inthe respect that the free ends of the side arms U are so spaced thatthere exist clearances X between the side arms U and the enlargement Pto protect the enlargement P against the wearing action of the sidearms.

In accordance with the present invention, the forward end of theaperture Q serves as a seat for a pin Y which carries at its ends ribs Zadapted to interlock with recesses or slots 6 in the inner surfaces ofthe side arms U to hold the yoke T in the retaining position.

Interposed between the shaft IV and the pin Y is a rubber buffer 0 whichhas arcuate grooves (Z and c in its rearward and forward endsrespectively to conform to the contours of the shaft W and the pin Y.The rubber buffer 0 projects with its ends beyond the sides of theenlargement P and bears against the inner surfaces of the side arms tohold said side arms out of contact with the front head. Any convenientmeans may be used for holding the shaft IV, the pin Y and the buffer 0fixedly in the aperture Q. In the present instance a bolt f is disposedin a hole 9 which extends longitudinally through the enlargement P andsaid bolt engages notches h, j and Z: in the shaft, the buffer and thepin respectively to lock these elements in the aperture Q.

In assembling the retainer on the front head, the pin Y and the buffer 0may first be placed in the aperture Q. The yoke T may then be placed insuch position that the holes V in the side arms will register with theuppermost end of the aperture Q. The shaft WV may now be inserted in theaperture and the holes wherein it will be held by the buffer 0. Afterthese parts have been thus arranged, the bolt 7 can be inserted in thehole 9 to engage the notches h, j and k for securing the pin, the shaftand the buffer in place.

In the retaining position of the retainer the ribs Z will engage therecesses Z) to hold the yoke securely in the retaining position.Whenever it is desired to change the drill steel, the retainer may berocked about the shaft V for a distance sufficient to remove the yoke Tout of the path of the collar O of the drill steel. The drill steel maythen be readily removed from the front head. After another drill steelhas been substituted therefor, the yoke may again be rocked to theretaining position. v

From the foregoing description, it will be readily seen that the fronthead is entirely protected against any form of wear by the retainer.This is due to the fact that no part of the retainer is permitted tocome into contact with the front head and any wear which may resulteither from the ordinary use of the retainer or from the effects ofvibration set up in the drill will be confined exclusively to thecomparatively inexpensive parts of the retainer and its adjuncts. Whenthese parts become unfit for use they may be readily replaced at acomparatively small expense and with a minimum expenditure of time.

I claim:

1. A steel retainer for a rock drill, comprising in combination with afront head and a collared drill steel, an enlargement on the front headhaving an aperture, a yoke for retaining the drill steel in the fronthead, side arms on the yoke, a shaft in the aperture and extend-ing intothe arms to act as a pivot for the yoke, a pin in the aperture to engagethe side arms for holding the yoke in the retaining position, and arubber buffer interposed between the shaft and the pintocushion theyoke.

2. A steel retainer for a rock drill, con1- prising in combination witha front head and a collared drill steel, an enlargement on the fronthead having. an aperture, a yoke for retaining the drill steel in thefront head, side arms on the yoke having recesses in their innersurfaces, a shaft in the aperture and extending into the arms to act asa pivot for the yoke, a pin in the aperture extending into the reeessesto maintain the yoke in the retaining position, and a rubber bufferinterposed between the shaft and the pin to cushion the yoke.

3. A steel retainer for a rock drill, comprising in combination with afront head and a collared drill steel, an enlargement on the front headhaving an aperture, a yoke for retaining the drill steel in the fronthead, side arms on the yoke having recesses in their inner surfaces, ashaft in the aperture extending through the side arms to act as a pivotfor the yoke, a pin in the aperture having ribs to engage the recessesfor holding the yoke in the retaining position, and a rubber bufferinterposed between the shaft and the pin to cushion the yoke. I

4. A steel retainer for a rock drill, comprising in combination with afront head and a collared drillsteel, an enlargement on the front headhaving an aperture, a yoke for retaining the drill steel in the fronthead, side arms on the yoke having recesses in their inner surfaces, ashaft in the aperture extending through the side arms to act as a pivotfor the yoke, a pin in the aperture having ribs to engage the recessesfor holding the yoke in the retaining position, a rubber bufferinterposed between the shaft and the pin to cushion the yoke, saidbuffer project-ing with its ends from the aperture to bear against theside arms for holding said side arms free from contact with theenlargement, and means for securing the shaft, the buffer and the pinfixedly in the aperture.

In testimony whereof I have signed this specification.

FRED M. SLATER.

